1. Field
The embodiments discussed herein are related to a network connection device which performs data transmission and reception processing and a signal processing method in the device.
2. Description of the Related Art
Conventional methods for managing a SONET/SDH (Synchronous Optical Network/Synchronous Digital Hierarchy) communication network include supporting GMPLS (Generalized Multi-Protocol Label Switching) and supporting OSI (Open Systems Interconnection). Some communication protocols are used in combination in the entire network.
Such a SONET/SDH communication network is managed by a piece of monitor and control equipment called an NMS (Network Management System).
At this time, a SDCC (Section Data Communication Channel) prepared in a section overhead of a SONET/SDH frame is used for communication between an NMS and a transmission device and communication between transmission devices.
A protocol used in a SDCC depends on whether a transmission device supports GMPLS or OSI. A TCP/IP protocol is used between transmission devices supporting GMPLS while an OSI protocol is used between transmission devices supporting OSI.
A protocol used by a transmission device serving as an object to be monitored and controlled needs to be used in a control signal to be transmitted by an NMS.
Accordingly, an NMS needs to be installed for each network group in which a common protocol is used in order to manage, e.g., the whole of a network where networks to which GMPLS-based management is applied and networks to which OSI-based management is applied are mixed. In this case, installation of NMSs entails a lot of costs and requires administrators for operating the NMSs to be stationed.
Japanese Laid-open Patent Publication No. 2004-524784 discloses an OSI tunnel which encapsulates an IP packet in an OSI packet and allows the OSI packet to pass through a DCN (Data Communication Network) supporting OSI.
The OSI tunnel makes it possible to monitor and control transmission devices supporting GMPLS by one NMS. The reduction in the number of NMSs leads to a reduction in costs and workforce.